THE SOLAR SYSTEM:
👉 Our solar system consists of the sun, eight planets, satellites, asteroids, and meteoroids. We often call it the solar family, with the sun as its head.
👉 The sun is in the center of our solar system.
👉 It is huge and made up of extremely hot gases.
👉 It is the ultimate source of heat and light for the solar system.
👉 The sun is about 150 million km away from the earth.
👉 In our solar system, there are eight planets.
👉 The eight planets are in order of their distance from the sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
👉 Planets move around the sun in a fixed path called orbits.
👉 Mercury is the nearest and Neptune is the farthest from the sun.
👉 Jupiter is the largest planet in our solar system.
👉It is the third nearest planet from the sun and the fifth-largest planet in our solar system.
👉The earth is the unique planet of our solar system because conditions favourable to support life are probably found only on the earth.
👉It is also called a blue planet because its two-thirds of surface is covered by water.
👉Its shape is geoid.
👉Our earth has only one satellite, that is, the moon.
👉Its diameter is only one-quarter that of the earth.
👉It is about 3,84,400 km away from us.
👉The moon moves around the earth in about 27 days.
👉The moon does not have conditions favourable for life.
👉There are numerous tiny bodies that also move around the sun, these are called asteroids.
👉 They are found between the orbits of Mars and Jupiter.
👉The small pieces of rocks which move around the sun are called meteoroids.
👉 When a meteoroid enters the earth’s atmosphere, it heats up due to friction from the air. It causes a flash of light.
👉A galaxy is a huge system of billions of stars, and clouds of dust and gases.
👉 Our solar system is a part of the Milky way (Akash Ganga) galaxy.
👉 There are millions of such galaxies that make the Universe.
👉The sun, the moon, and all those objects shining in the night sky are called celestial bodies.
👉A star is a celestial body that is made up of gases that have their own heat and light, which they emit in large amounts.
👉A group of visible stars that form various patterns is called a constellation.
👉 Ursa Major or Big Bear is one such constellation.
👉 When the moon is visible from the earth as a full sphere, is called full moon night or Poornima.
👉 You can see the full moon only once in about a month’s time.
👉A fortnight later, you can not see it at all. It is called New Moon night or Amavasya.
👉In ancient times, people used to determine directions during the night with the help of stars. The North star indicates the north direction. It is called Pole star. IT always remains in the same position in the sky.
👉A satellite is a celestial body that moves around the planets in the same way as the planets move around the sun.
SOME IMPORTANT FACTS:
👉 A human-made satellite is an artificial body. It is designed by scientists to gather information about the universe or form communication.
👉 Neil Armstrong was the first to step on the surface of the moon on 20 July 1969.
👉 Light travels at a speed of about 300,000 km per second.